Type Geological formation Other Chert, siltstone Named by A. McGugan, 1963 Named for Mount Ishbel | Underlies Spray River Group Country Canada Primary Sandstone Overlies Tunnel Mountain Formation | |
 | ||
Thickness up to 427 metres (1,400 ft) Region Western Canadian Sedimentary Basin | ||
The Ishbel Group is a stratigraphical unit of Permian age in the Western Canadian Sedimentary Basin.
Contents
It was first defined by A. McGugan in 1963. It is named for Mount Ishbel of the Sawback Range, and parts of the group were first described in the vicinity of the mountain (Ranger Canyon, Johnston Canyon).
Lithology
The Ishbel Group is composed of carbonate, sandstone, chert and siltstone.
Paleontology
The Ishbel Group was laid down under Phosphoria depositional conditions; among the fossils that can be found are productid, chonetid and spiriferid brachiopods, omphalotrochid gastropod and edestid elasmobranch fish.
Distribution
The Ishbel Group reaches a maximum thickness of 427 metres (1,400 ft). It occurs in the front ranges of the Canadian Rockies as far north as the Peace River.
Relationship to other units
The Ishbel Group is disnconformably overlain by the Spray River Group and unconformably overlays the Tunnel Mountain Formation and the Kananaskis Formation in Kananaskis Country.
It is equivalent to the Phosphoria Formation in Montana and Idaho.